Quick connect couplers have been used for a variety of purposes as shown by the following references. Each coupler design appears to be influenced by the end use utility.
Hand tool quick release couplers for a tool or frame and an extension handle are subjected to torque and lateral stresses. For example, painters working with rollers force the ends of the rollers against the ceiling/wall juncture to reduce the need for trim painting. They may paint a gutter with only a portion of a roller or use a roller which is not perpendicular to the handle. They may paint woven surfaces or press down to exhaust the final dabs of paint from the roller when they are running out of paint. All these activities place considerable stress on the coupler.
Further, the painter may work in close quarters with a high ceiling and need to switch quickly between the use of a short handle and one or more extension handles. With the modern insistence on productivity, newer approaches to couplers are necessary.
U.S. Pat. No. 4,663,796 issued to L. L. and M. M. Helling describes a handle, including a female member which is coupled with a male member attached to a tool. The male member includes a pointed projection with a groove into which ball bearings can fit. The female member utilizes a spring to force ball bearings in a locking mechanism into the groove and complete the coupling.
U.S. Pat. No. 4,132,489 issued to A. T. Berg Jr. teaches a quick release coupler for handle extensions shaped so that two ends of extensions are forced into the ends of the coupler. Latch mechanisms which fit into notches in the handle are the primary fasteners.
There are other types of couplers which do not undergo the stress exerted on tool and extension couplers. Examples, some complex, are described below:
U.S. Pat. No. 4,128,264 issued to W. G. Oldford teaches a quick release, rotatable fitting for fluid transmission tubing in which a male element with a terminal flange and cruciform slots is utilized as a locking element.
U.S. Pat. No. 3,887,222 issued to H. H. Hammond teaches a fluid transmission tubing coupling with a push-pull release. A male element stop ring is utilized to compress a female element compressible lock ring to enable the insertion of the male element. A cam, activated by further male element pressure, compresses the lock ring for separation of the elements.
U.S. Pat. No. 3,245,703 issued to R. S. Manley teaches a quick release pipe, e.g. garden hose, coupling with manually compressible latches as a locking mechanism.
U.S. Pat. No. 2,327,951 issued to J. Zaleske teaches a quick connect, rotating or nonrotating coupling for rods, tubes, etc passing through aircraft fire walls, etc. The device utilizes male and female members. The resilient female member is slotted and has internal groove into which an annular enlargment on the male member is forced. A nonflexible sleeve slides over the seated combination to lock the members together and is retracted to enable the male member to be retracted. The inclusion of projections on the male member which fit in the slots of the female member eliminates rotation of the elements.